Home
Search results “Not null index oracle”
Oracle - SQL - Not Null Constraint
 
05:14
Oracle - SQL - Not Null Constraint Watch more Videos at https://www.tutorialspoint.com/videotutorials/index.htm Lecture By: Mr. Anadi Sharma, Tutorials Point India Private Limited.
Oracle SQL Tutorial 21 - How to Create / Drop Indexes
 
03:58
In the last video, we wrote up the SQL to create three tables: CREATE TABLE users( user_id NUMBER, username VARCHAR2(50 CHAR) UNIQUE, CONSTRAINT users_pk PRIMARY KEY (user_id) ); CREATE TABLE projects( project_id NUMBER, Project_name VARCHAR2(50 CHAR) UNIQUE, creator VARCHAR2(50 CHAR) NOT NULL, CONSTRAINT projects_pk PRIMARY KEY (project_id), CONSTRAINT projects_users_fk FOREIGN KEY (creator) REFERENCES users (username) ON DELETE CASCADE ); CREATE TABLE project_users( project_id NUMBER NOT NULL REFERENCES projects (project_id) ON DELETE CASCADE, user_id NUMBER NOT NULL REFERENCES users (user_id) ON DELETE CASCADE, CONSTRAINT project_users_pk PRIMARY KEY (project_id, user_id) ); I'm going to increase the size of the users table a bit by adding a first and last name column. CREATE TABLE users( user_id NUMBER, username VARCHAR2(50 CHAR) UNIQUE, first_name VARCHAR2(50 CHAR), last_name VARCHAR2 (50 CHAR), CONSTRAINT users_pk PRIMARY KEY (user_id) ); But before we finish this design, we should consider indexing certain columns. What columns should we index? Well, as a reminder, the columns that are indexed by default are columns with the UNIQUE constraint, and those that are labeled as primary keys. Columns that are not indexed but often should be are those labeled as a foreign key. The column that jumps out the most to me is the creator column of the project table. It's the only foreign key that is not part of some index. Let's fix this by creating our first index. The way we do that is with the CREATE INDEX command. CREATE INDEX projects_creator_ix ON projects (creator) What naming convention are we following for the index? We are naming it by the table name, followed by an underscore, followed by the column, followed by an underscore, followed by an ix (for index). In this situation it does not apply, but if our foreign key column is labeled as UNIQUE, we can add the UNIQUE keyword like this: CREATE UNIQUE INDEX projects_creator_ix ON projects (creator) Now if you want to get rid of an INDEX, you can use this command: DROP INDEX projects_creator_ix Now, if we want to select data from the user table and the project table we can do that much faster. That's because the foreign key and column it references are both indexed and those are the columns we would do the join on. We will discuss how to do joins in a future video. So what are some potential problems with this database design? Overall, it is pretty good. With this design though we need to make sure there is no way for someone to update a user's username. In the next video we are going to discuss why. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Support me on Patreon! http://www.patreon.com/calebcurry Subscribe to my newsletter: http://bit.ly/JoinCCNewsletter Donate!: http://bit.ly/DonateCTVM2. ~~~~~~~~~~~~~~~Additional Links~~~~~~~~~~~~~~~ More content: http://CalebCurry.com Facebook: http://www.facebook.com/CalebTheVideoMaker Google+: https://plus.google.com/+CalebTheVideoMaker2 Twitter: http://twitter.com/calebCurry Amazing Web Hosting - http://bit.ly/ccbluehost (The best web hosting for a cheap price!)
Views: 10149 Caleb Curry
SQL Server 26 - PRIMARY KEY, NOT NULL, UNIQUE
 
03:36
In the last video we created our first table, but I want to give SQL Server some extra information so the database knows more about each of the columns. The first thing is to establish the primary key. To do this all we do is add PRIMARY KEY after the column we want to be the primary key. Simple enough. When we add a constraint right after the column like this, it is often called a column attribute. CREATE TABLE Animals( ID INT PRIMARY KEY, Name VARCHAR(50), Species VARCHAR(50) ); Additionally, if you are using an ID column, it is best to have it labeled as the IDENTITY column. That way, SQL Server will automatically increment the number. CREATE TABLE Animals( ID INT PRIMARY KEY IDENTITY, Name VARCHAR(50), Species VARCHAR(50) ); The other attributes we've discussed in this series are NOT NULL and UNIQUE. We can make the name NOT NULL and the species NOT NULL. We don't have a good column for UNIQUE, so let's add one: CREATE TABLE Animals( ID INT PRIMARY KEY IDENTITY, Name VARCHAR(50) NOT NULL, Species VARCHAR(50) NOT NULL, ContactEmail VARCHAR(50) NOT NULL UNIUQE ); You can see that it is very easy to add multiple column attributes to a column. Just separate them by spaces. The order does not matter. Also, when you say primary key the column is automatically NOT NULL and UNIQUE. There are other attributes you can use including DEFAULT, FOREIGN KEY, and SPARSE. DEFAULT will give a value for a column if you do not put anything in yourself. Foreign keys are used to reference other columns. SPARSE is an attribute we haven't discussed. You can use SPARSE if most of the rows are going to have a NULL for a column and it saves storage space, but we will worry about that in another video. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Support me! http://www.patreon.com/calebcurry Subscribe to my newsletter: http://bit.ly/JoinCCNewsletter Donate!: http://bit.ly/DonateCTVM2. ~~~~~~~~~~~~~~~Additional Links~~~~~~~~~~~~~~~ More content: http://CalebCurry.com Facebook: http://www.facebook.com/CalebTheVideoMaker Google+: https://plus.google.com/+CalebTheVideoMaker2 Twitter: http://twitter.com/calebCurry Amazing Web Hosting - http://bit.ly/ccbluehost (The best web hosting for a cheap price!)
Views: 6234 Caleb Curry
Oracle Database Indexes: Myths, Tips and Tricks
 
09:04
In this tutorial, OCM John Watson will - via demonstrations - debunk these myths: Myth #1: Oracle Database does not index NULL Myth #2: A search that includes wildcards can't use an index if the wildcard precedes the string. Myth #3: Oracle will not use a function-based index unless the FBI is coded in the predicate. Myth #4: Indexes always help. The more indexes the better. See http://skillbuilders.com/free-oracle-tutorials for gigabytes of free Oracle video tutorials.
Views: 16457 SkillBuilders
13.50 NOT NULL, DEFAULT, CHECK, CREATE DOMAIN
 
10:46
Komplette Liste der Videos und zusätzliches Material auf http://datenbankenlernen.de Informatik, Uni Saarland: Bachelor: http://www.cs.uni-saarland.de/index.php?id=52&L=1&source=1350 Master: http://www.cs.uni-saarland.de/index.php?id=132&L=1&source=1350 Ph.D./Grad School: http://gradschool.cs.uni-saarland.de/&source=1350
Oracle SQL Tutorial 20 - How to Create Composite Primary Keys
 
07:02
This video is going to be a tutorial on how to create composite and compound keys. The difference between a composite and compound key is that a composite key can consist of any columns while a compound key has to consist of columns that are all keys themselves. We will be working with a compound key because we are going to be using the an intermediary table that has two foreign keys. The combination of both of the keys have to be unique. First, if we have any other CREATE TABLE commands, we are going to comment those out. We will space out the CREATE TABLE to have each column on a line, then we will add constraints as needed. CREATE TABLE project_users( project_id, user_id ) Now, let's add the data types: CREATE TABLE project_users( project_id NUMBER, user_id NUMBER } Now, what about some column attributes? I'm going to make both of the columns NOT NULL because we always want the rows to have a user and a project: CREATE TABLE project_users( project_id NUMBER NOT NULL, user_id NUMBER NOT NULL } Now, let's add the foreign key constraints. Now, what do we name these? We are going to add a primary key that covers both of these columns, so I'm going to be a sinner and not give these constraints names: CREATE TABLE project_users( project_id NUMBER NOT NULL REFERENCES projects (project_id), user_id NUMBER NOT NULL REFFERENCES users (user_id) ) Now, the way we have it now is that if we delete a project in the project table, and there are any rows in the project_users table, it will throw an error and prevent deletion. I would prefer for it to also delete any project members. That would make sense because if you delete a project we want it to delete the associate between that project and certain users. The same goes for if we delete a user, we want their association with a certain project to be deleted. To do this, we need to add the ON DELETE command: CREATE TABLE project_users( project_id NUMBER NOT NULL REFERENCES projects (project_id) ON DELETE CASCADE, user_id NUMBER NOT NULL REFERENCES users (user_id) ON DELETE CASCADE, ) Finally, let's learn how to create a compound or composite key. literally, the only difference is that you put a comma and add the second table inside of the parenthesis. CREATE TABLE project_users( project_id NUMBER NOT NULL REFERENCES projects (project_id) ON DELETE CASCADE, user_id NUMBER NOT NULL REFERENCES users (user_id) ON DELETE CASCADE, CONSTRAINT project_users_pk PRIMARY KEY (project_id, user_id) ) Now, the combination of project_id and user_id cannot be null, is always unique, and has an index. The only thing we should do now is add a few indexes. We aren't done yet...In the next video we are going to figure out what columns would benefit from indexes and we'll add them to it. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ HELP ME! http://www.patreon.com/calebcurry Subscribe to my newsletter: http://bit.ly/JoinCCNewsletter Donate!: http://bit.ly/DonateCTVM2. ~~~~~~~~~~~~~~~Additional Links~~~~~~~~~~~~~~~ More content: http://CalebCurry.com Facebook: http://www.facebook.com/CalebTheVideoMaker Google+: https://plus.google.com/+CalebTheVideoMaker2 Twitter: http://twitter.com/calebCurry Amazing Web Hosting - http://bit.ly/ccbluehost (The best web hosting for a cheap price!)
Views: 12984 Caleb Curry
NOT NULL, DEFAULT, CHECK Constraints (Domain Integrity) in SQL Server
 
16:55
NOT NULL, DEFAULT, CHECK Constraints (Domain Integrity) in SQL Server Check my blog for more on Constraints and related sample SQL Queries: http://sqlwithmanoj.com/2010/11/23/integrity-constraints/ Check the whole "SQL Server Basics" series here: https://www.youtube.com/playlist?list=PLU9JMEzjCv14f3cWDhubPaddxRvx1reKR Check my SQL blog at: http://sqlwithmanoj.com/ Check my SQL FB Page at: https://www.facebook.com/sqlwithmanoj
Views: 16737 SQL with Manoj
Oracle SQL Tuning with NOT NULL Constraints
 
02:28
Learn how to tune SQL with Constraints! In this lesson (3 of 5), OCM John Watson from SkillBuilders demonstrates how to improve query performance by adding not null constraints. See all lessons, free at http://www.skillbuilders.com/oracle-database-sql-tuning-with-constraints.
Views: 410 SkillBuilders
Create, Alter, Drop Not Null constraint in SQL Server - Part 10 Tamil
 
11:04
Subscribe to IT PORT : https://www.youtube.com/c/itport28 SQL Server Tutorial in Tamil : https://www.youtube.com/playlist?list=PLouAaeZ4xQ64enJDwWVvN3KduuZRlUrb3 SQL Server Concepts in Tamil : https://www.youtube.com/playlist?list=PLouAaeZ4xQ67kdNIByJKAGBIBhor_h4Hs SQL Server Analytic Functions in Tamil : https://www.youtube.com/playlist?list=PLouAaeZ4xQ65XIU5azEUgLVrBKEl-jWMV SQL Server Tutorial : https://www.youtube.com/playlist?list=PLouAaeZ4xQ66AYrzPtxt2SeeR4UABcBcO SQL Server Concepts : https://www.youtube.com/playlist?list=PLouAaeZ4xQ66zRe8-nDDy-YHY2o0rmbn4 SQL Server Analytic Functions : https://www.youtube.com/playlist?list=PLouAaeZ4xQ64hTsEdhLsVBquE1vERWngX NULL is the term used to represent a missing value. A NULL value in a table is a value in a field that appears to be blank. A field with a NULL value is a field with no value. NULL value is different than a zero value or a field that contains spaces By default, a column can hold NULL values. The NOT NULL constraint enforces a column to NOT accept NULL values. This enforces a field to always contain a value, which means that you cannot insert a new record, or update a record without adding a value to this field By default, a column can hold NULL values. The NOT NULL constraint enforces a column to NOT accept NULL values. This enforces a field to always contain a value, which means that you cannot insert a new record, or update a record without adding a value to this field Explained in Tamil
Views: 394 IT Port
What is BLOCK RANGE INDEX? What does BLOCK RANGE INDEX mean? BLOCK RANGE INDEX meaning
 
08:12
What is BLOCK RANGE INDEX? What does BLOCK RANGE INDEX mean? BLOCK RANGE INDEX meaning - BLOCK RANGE INDEX definition - BLOCK RANGE INDEX explanation. Source: Wikipedia.org article, adapted under https://creativecommons.org/licenses/by-sa/3.0/ license. SUBSCRIBE to our Google Earth flights channel - https://www.youtube.com/channel/UC6UuCPh7GrXznZi0Hz2YQnQ A Block Range Index or BRIN is a database indexing technique. They are intended to improve performance with extremely large tables. BRIN indexes provide similar benefits to horizontal partitioning or sharding but without needing to explicitly declare partitions. A BRIN is applicable to an index on a table that is large and where the index key value is easily sorted and evaluated with a MinMax function. BRIN were originally proposed by Alvaro Herrera of 2ndQuadrant in 2013 as 'Minmax indexes'. Implementations thus far are tightly coupled to internal implementation and storage techniques for the database tables. This makes them efficient, but limits them to particular vendors. So far PostgreSQL is the only vendor to have announced a live product with this specific feature, in PostgreSQL 9.5. Other vendors have described some similar features, including Oracle, Netezza 'zone maps', Infobright 'data packs', MonetDB and Apache Hive with ORC/Parquet. BRIN operate by "summarising" large blocks of data into a compact form, which can be efficiently tested to exclude many of them from a database query, early on. These tests exclude a large block of data for each comparison. By reducing the data volume so early on, both by representing large blocks as small tuples, and by eliminating many blocks, BRIN substantially reduce the amount of detailed data that must be examined by the database node on a row-by-row basis. Data storage in large databases is layered and chunked, with the table storage arranged into 'blocks'. Each block contains perhaps 1MB in each chunk and they are retrieved by requesting specific blocks from a disk-based storage layer. BRIN are a lightweight in-memory summary layer above this: each tuple in the index summarises one block as to the range of the data contained therein: its minimum and maximum values, and if the block contains any non-null data for the column(s) of interest. Unlike a traditional index which locates the regions of the table containing values of interest, BRIN act as "negative indexes", showing the blocks that are definitely not of interest and thus do not need to be processed further. Some simple benchmarks suggest a five-fold improvement in search performance with an index scan, compared to the unindexed table. Compared to B-trees, they avoid their maintenance overhead. As BRIN are so lightweight, they may be held entirely in memory, thus avoiding disk overhead during the scan. The same may not be true of B-tree: B-tree requires a tree node for every approximately N rows in the table, where N is the capacity of a single node, thus the index size is large. As BRIN only requires a tuple for each block (of many rows), the index becomes sufficiently small to make the difference between disk and memory. For a 'narrow' table the B-tree index volume approaches that of the table itself; the BRIN may be only 5-15% of it. A large database index would typically use B-tree algorithms. BRIN is not always a substitute for B-tree, it is an improvement on sequential scanning of an index, with particular (and potentially large) advantages when the index meets particular conditions for being ordered and for the search target to be a narrow set of these values. In the general case, with random data, B-tree may still be superior. A particular advantage of the BRIN technique, shared with Oracle Exadata's Smart Scanning, is in the use of this type of index with Big Data or data warehousing applications, where it is known that almost all of the table is irrelevant to the range of interest. BRIN allows the table to be queried in such cases by only retrieving blocks that may contain data of interest and excluding those which are clearly outside the range, or contain no data for this column. A regular problem with the processing of large tables is that retrieval requires the use of an index, but maintaining this index slows down the addition of new records. Typical practices have been to group additions together and add them as a single bulk transaction, or to drop the index, add the batch of new records and then recreate the index. Both of these are disruptive to simultaneous read / write operations and may not be possible in some continuously-operating businesses. With BRIN, the slowdown from maintaining the index is much reduced compared to B-tree. Wong reports that B-tree slowed down additions to an unindexed 10GB table by 85%, but a comparable BRIN only had an overhead of 11%. BRIN may be created for extremely large data where B-tree would require horizontal partitioning.....
Views: 292 The Audiopedia
Oracle - SQL - Creating Sequences
 
07:31
Oracle - SQL - Creating Sequences Watch more Videos at https://www.tutorialspoint.com/videotutorials/index.htm Lecture By: Mr. Anadi Sharma, Tutorials Point India Private Limited.
Oracle Database | Bangla Tutorials 23 :: Constraint Not null
 
01:33
www.facebook.com/oracle.shohag Email : [email protected] Website : www.oraclebangla.com Topics : Constraint Not null
Views: 1050 Oracle Bangla
4 - T-SQL - CONSTRAINTS (Restrições) - PRIMARY KEY, NOT NULL, etc - SQL Server
 
09:39
T-SQL - CONSTRAINTS (Restrições) Neste vídeo vamos mostrar como configurar as constraints PRIMARY KEY, NOT NULL, UNIQUE, FOREIGN KEY, CHECK, DEFAULT ao criarmos tabelas em bancos de dados com SQL Server Mais sobre constraints no SQl Server aqui: http://www.bosontreinamentos.com.br/sql-com-sql-server/4-t-sql-constraints-restricoes-primary-key-not-null-etc-sql-server/ Contribua com a Bóson Treinamentos!: Clube de Contribuições do Catarse: https://www.catarse.me/bosontreinamentos Outras formas de contribuição: http://www.bosontreinamentos.com.br/contribuir/ Por Fábio dos Reis Bóson Treinamentos: http://www.bosontreinamentos.com.br Facebook: https://www.facebook.com/bosontreinamentos/ Pinterest: https://br.pinterest.com/bosontreina/ Twitter: https://twitter.com/bosontreina Instagram: https://www.instagram.com/bosontreinamentos/ LInkedin: https://www.linkedin.com/in/f%C3%A1bio-dos-reis-06ba192a/ Outros projetos do autor: Diário do Naturalista: http://www.diariodonaturalista.com.br
Views: 45386 Bóson Treinamentos
Oracle - SQL - Check Constraint
 
04:15
Oracle - SQL - Check Constraint Watch more Videos at https://www.tutorialspoint.com/videotutorials/index.htm Lecture By: Mr. Anadi Sharma, Tutorials Point India Private Limited.
Table Constraints in SQL: NOT NULL, DEFAULT, UNIQUE, and CHECK
 
03:44
This SQL tutorial discusses the common constraints one can place on a table: NOT NULL, DEFAULT, UNIQUE, and CHECK, including the purpose of each constraint, as well as how to apply each constraint to a table during table creation. 0:24 NOT NULL Constraint 0:56 DEFAULT Constraint 2:03 UNIQUE Constraint 2:34 CHECK Constraint
Views: 8946 1Keydata
4- Oracle DB - Primary Foreign Unique Not Null Check Composite Keys Table Level and Column Level.avi
 
37:25
Oracle DB - Primary Foreign Unique Not Null Check Composite Keys Table Level and Column Level
Views: 2709 Adel Sabour
TUTORIAL MEMBUAT PHYSICAL DATABASE DARI ORACLE SQL DEVELOPER
 
38:24
Tutorial kasar : -sqlplus oa/oa -connect as sysdba; -create user paijo identified by paijo; -grant all privilege to paijo; -connect paijo/paijo -show user //lalu buat file di oracle home dengan nama paijo.sql dengan isi: ========================================= DROP TABLE "DOKTERS"; DROP TABLE "PASIENS"; DROP TABLE "DIAGNOSAS"; CREATE TABLE DOKTERS ("ID_DTR" VARCHAR (7), "NAMA" VARCHAR (25) NOT NULL, "ALAMAT" VARCHAR (30) NOT NULL, CONSTRAINT "ID_DTR_PK" PRIMARY KEY ("ID_DTR") USING INDEX ENABLE); CREATE TABLE PASIENS ("ID_PSN" VARCHAR (9), "NAMA" VARCHAR (25) NOT NULL, "ALAMAT" VARCHAR (30), CONSTRAINT "ID_PSN_PK" PRIMARY KEY ("ID_PSN") USING INDEX ENABLE); CREATE TABLE DIAGNOSAS ("TANGGAL" DATE, "HASIL" VARCHAR (30) NOT NULL, "ID_DTR" VARCHAR (7), "ID_PSN" VARCHAR (9), CONSTRAINT "TGL_PK" PRIMARY KEY ("TANGGAL", "ID_DTR", "ID_PSN") USING INDEX ENABLE); ====================================== [email protected] -desc dokters; -desc pasiens; -desc diagnosas; //lalu buat file di oracle home dengan nama alter_paijo.sql dengan isi: ===================================== ALTER TABLE DIAGNOSAS ADD CONSTRAINT "DIA_ID_DTR" FOREIGN KEY ("ID_DTR") REFERENCES DOKTERS ("ID_DTR"); ALTER TABLE DIAGNOSAS ADD CONSTRAINT "DIA_ID_PSN" FOREIGN KEY ("ID_PSN") REFERENCES PASIENS ("ID_PSN"); =================================== [email protected]_paijo.sql //lalu buat file di oracle home dengan nama isi_paijo.sql dengan isi: =================================== INSERT INTO DOKTERS VALUES('D100799','PAIJO','JALAN IN AJA'); INSERT INTO DOKTERS VALUES('D120498','PAINO','JALAN JALAN'); INSERT INTO DOKTERS VALUES('D071297','PAIWO','JALAN YANG BENAR'); INSERT INTO PASIENS VALUES('PSN130193','JARWO','JALAN LURUS'); INSERT INTO PASIENS VALUES('PSN040494','JARVIS','JALAN GRAK'); INSERT INTO PASIENS VALUES('PSN121212','JARAN','JALAN BERBELOK'); INSERT INTO DIAGNOSAS VALUES(TO_DATE('18-12-18','DD-MM-YY'),'PARU KERING','D100799','PSN130193'); INSERT INTO DIAGNOSAS VALUES(TO_DATE('19-12-18','DD-MM -YY'),'KAGETAN','D120498','PSN040494'); INSERT INTO DIAGNOSAS VALUES(TO_DATE('20-12-18','DD-MM-YY'),'GATEL','D071297','PSN121212'); ================================ [email protected]_paijo.sql -select * from dokters; -select * from pasiens; -select * from diagnosas; //lalu buat file di oracle home dengan nama select_paijo.sql dengan isi: ============================== SELECT DOKTERS.ID_DTR, DOKTERS.NAMA, PASIENS.ID_PSN, PASIENS.NAMA, DIAGNOSAS.TANGGAL, DIAGNOSAS.HASIL FROM DOKTERS, PASIENS, DIAGNOSAS WHERE DOKTERS.ID_DTR = DIAGNOSAS.ID_DTR AND PASIENS.ID_PSN= DIAGNOSAS.ID_PSN =========================== [email protected]_paijo.sql
SQL Constraints - NOT NULL , UNIQUE , PRIMARY KEY , FOREIGN KEY , CHECK , INDEX , default
 
10:17
SQL is a standard Structured query language for storing, manipulating and retrieving data in databases. NOT NULL , UNIQUE , PRIMARY KEY , FOREIGN KEY , CHECK , INDEX , default 1) NOT NULL - Ensures that a column cannot have a NULL value 2) UNIQUE - Ensures that all values in a column are different 3) PRIMARY KEY - A combination of a NOT NULL and UNIQUE. Uniquely identifies each row in a table 4) FOREIGN KEY - Uniquely identifies a row/record in another table. The table containing the foreign key is called the child table, and the table containing the candidate key is called the referenced or parent table. prevents invalid data and destroy links between tables. 5) CHECK - Ensures that all values in a column satisfies a specific condition 6) DEFAULT - Sets a default value for a column when no value is specified 7) INDEX - Used to create and retrieve data from the database very quickly.
Views: 52 R K
Constraints Part-2 NOT NULL , UNIQUE , PRIMARY KEY , FOREIGN KEY , CHECK , INDEX , default
 
13:22
SQL is a standard Structured query language for storing, manipulating and retrieving data in databases. NOT NULL , UNIQUE , PRIMARY KEY , FOREIGN KEY , CHECK , INDEX , default 1) NOT NULL - Ensures that a column cannot have a NULL value 2) UNIQUE - Ensures that all values in a column are different 3) PRIMARY KEY - A combination of a NOT NULL and UNIQUE. Uniquely identifies each row in a table 4) FOREIGN KEY - Uniquely identifies a row/record in another table. The table containing the foreign key is called the child table, and the table containing the candidate key is called the referenced or parent table. prevents invalid data and destroy links between tables. 5) CHECK - Ensures that all values in a column satisfies a specific condition 6) DEFAULT - Sets a default value for a column when no value is specified 7) INDEX - Used to create and retrieve data from the database very quickly.
Views: 39 R K
mysql tutorial for beginners (6/8) : Indexes
 
05:48
mysql tutorial for beginners (6/8) : Indexes As things stand, the table students works and can be searched without problem by MySQL—until it grows to more than a couple of hundred rows, At that point, database accesses will get slower and slower with every new row added, because MySQL has to search through every row whenever a query is issued. This is like searching through every book in a library whenever you need to look something up. Of course, you don’t have to search libraries that way, because they have either a card index system or, most likely, a database of their own. The way to achieve fast searches is to add an index, either when creating a table or at any time afterward. But the decision is not so simple. For example, there are different index types such as a regular INDEX, PRIMARY KEY, and FULLTEXT. Also, you must decide which columns require an index, a judgment that requires you to predict whether you will be searching any of the data in that column. And even when you’ve decided that, you still have the option of reducing index size by limiting the amount of each column to be indexed. If we imagine the searches that may be made on the students table, it becomes apparent that all of the columns may need to be searched. Anyway, go ahead and add an index to each of the columns, using the commands: ALTER TABLE students ADD INDEX(name(3)); An alternative to using ALTER TABLE to add an index is to use the CREATE INDEX command. They are equivalent, except that CREATE INDEX cannot be used for creating a PRIMARY KEY CREATE INDEX surname ON students (surname(5)); DESCRIBE students; These commands create indexes on both the name and surname columns, limiting name index to only the first 3 characters, and surname index to the first 5 characters. For instance, when MySQL indexes the following name: SAFAA It will actually store in the index only the first 3 characters: SAF This is done to minimize the size of the index, and to optimize database access speed. DESCRIBE command shows the key MUL for each column. This key means that multiple occurrences of a value may occur within that column, which is exactly what we want, as name or surname may appear many times. You don’t have to wait, until after creating a table to add indexes. In fact, doing so can be time-consuming, as adding an index to a large table can take a very long time. Therefore, let’s look at a command that creates the table students with indexes already in place. CREATE TABLE students ( Id_studnet SMALLINT UNSIGNED NOT NULL AUTO_INCREMENT, name VARCHAR(10) NOT NULL, surname VARCHAR(20) NOT NULL, email VARCHAR(30) NOT NULL, INDEX(name(3)), INDEX(surname(5)), ,PRIMARY KEY(id_studnet),UNIQUE(email)); Another important index, PK, its single unique key for each student to enable instant accessing of a row. The importance of having a key with a unique value for each row will come up when we start to combine data from different tables. You can add PK, while you create the table at the first time, or later by issuing the following command: ALTER TABLE students ADD PRIMARY KEY(id_student); The last important index, FULLTEXT index Unlike a regular index, MySQL’s FULLTEXT allows super-fast searches of entire columns of text. It stores every word in every data string in a special index that you can search using “natural language,” in a similar manner to using a search engine. It’s not strictly true that MySQL stores all the words in a FULLTEXT index, because it has a built-in list of more than 500 words that it chooses to ignore because they are so common that they aren’t very helpful for searching anyway. This list, called stopwords, includes the, as, is, of, and so on. The list helps MySQL run much more quickly when performing a FULLTEXT search and keeps database sizes down. FULLTEXT indexes can be created for CHAR, VARCHAR, and TEXT columns only. A FULLTEXT index definition can be given in the CREATE TABLE statement when a table is created, or added later using ALTER TABLE (or CREATE INDEX). Adding a FULLTEXT index to the table students for the columns name and surname ALTER TABLE classics ADD FULLTEXT(name,surname); this index is in addition to the ones already created and does not affect them You can now perform FULLTEXT searches across this pair of columns. If you find that MySQL is running slower than you think it should be when accessing your database, the problem is usually related to your indexes. Either you don’t have an index where you need one, or the indexes are not optimally designed. Tweaking a table’s indexes will often solve such a problem. In the next tutorial, we will learn about, using FOREIGN KEY Constraints and how to join tables together. Subscribe for more: ---------------------------------------------------------------------------- https://www.youtube.com/subscription_center?add_user=saf3al2a SWE.Safaa Al-Hayali - saf3al2a
Views: 31109 Safaa Al-Hayali
Oracle Interview Question - oracle index related questions - BTREE index in oracle
 
23:14
Oracle Interview Question - oracle index related questions 1. What is Index? How to create index? 2. What are the types of index? 3. How to find the list of indexes for a given table? 4. Explain B-tree index 5. Explain Bitmap index 6. Explain "Function based" index 7. Explain "Reverse Key" index 8. When to choose what type of index? 9. How to know index is being used? 10. How to monitor index usage? 11. What are the advantages/drawbacks of indes? List of all the SQL and PLSQL interview questions @ https://easy-learning-tech.blogspot.com/p/oracle-sql-plsql-interview-questions.html
Views: 1707 Siva Academy
SQL NOT NULL Constraint Telugu | WHAT IS NOT NULL constraints-vlr training
 
07:52
For All sql videos in telugu http://www.vlrtraining.in/sql-training-videos-telugu/ In Telugu: SQL NOT NULL Constraint Telugu WHAT IS NOT NULL constraints? MySQL NOT NULL Constraint sql not null query not null in mysql MySQL NOT NULL Constraint The NOT NULL constraint enforces a column to NOT accept NULL values. This enforces a field to always contain a value, which means that you cannot insert a new record, or update a record without adding a value to this field. In English: download sql study material Website: http://www.vlrtrain.in/2016/09/download-sql-files.html Learn SQL sql tutorial for beginners sql commands oracle sql tutorial sql tutorial advanced mysql tutorial sql tutorial video SQL Tutorial, Tutorials SQL
Views: 872 VLR Training
SQL with Oracle 10g XE - Using ALTER TABLE to Modify Table Columns
 
05:23
In this video I use the ALTER TABLE command to modify an existing field column. The command will allow you to change the data types, whether the field can be null, or even the primary key. When using the ALTER TABLE command you would use the keyword MODIFY to make changes to an existing column. Be careful when changing a data type of the null field as existing data may cause an error if not in compliance with the new change. The code I used to alter the Books table is : ALTER TABLE BOOKS MODIFY ISBN_10 VARCHAR(13); This video is part of a series of videos with the purpose of learning the SQL language. For more information visit Lecture Snippets at http://lecturesnippets.com.
Views: 16412 Lecture Snippets
oracle interview question oracle index function based index
 
08:33
Title: Oracle Interview Question - oracle index related questions - Function based index in oracle Description: Oracle Interview Question - oracle index related questions 1. What is Index? How to create index? 2. What are the types of index? 3. How to find the list of indexes for a given table? 4. Explain B-tree index 5. Explain Bitmap index 6. Explain "Function based" index 7. Explain "Reverse Key" index 8. When to choose what type of index? 9. How to know index is being used? 10. How to monitor index usage? 11. What are the advantages/drawbacks of indexes?
Views: 981 Siva Academy
T-SQL - NOT NULL Constraints
 
03:10
T-SQL - NOT NULL Constraints Watch more Videos at https://www.tutorialspoint.com/videotutorials/index.htm Lecture By: Mr. Anadi Sharma, Tutorials Point India Private Limited
Oracle SQL Tutorial 6 - Relationships and Primary and Foreign Keys - Database Design Primer 3
 
29:40
HAPPY VALENTINES DAY!!! Let's talk relationships.. This is the 6th video in your Oracle Database series. We are discussing database relationships which are a key feature of relational database management systems. We first discussed entities and attributes. I talked about how each entity is assigned a table and each attribute is a column within a table. We moved on to the three kinds of relationships. The first was one-to-one. This describes an entity and an attribute. A piece of data that is exclusive to an entity is, by definition, an attribute of that entity. This is stored in one table with the attribute being a column within this table. The second relationship is one-to-many. This relationship is between two entities. The way we properly store this in a database is using a foreign key in the child table. Remember, the child table is the entity on the many side of the one-to-many relationship. Every row within the child table will have a value for the foreign key that references a primary key in the parent table. This assumes that the foreign key field is not optional (NOT NULL). If the foreign key is optional, than a reference is not required but any reference must be valid. The third kind of relationship is a many-to-many relationship. In this situation, we need 3 tables. The many-to-many relationship is broken up into two one-to-many relationships. The intermediary table will associate each entity from one table with the appropriate entities in the other table. There is debate as to whether this table needs a primary key. This is because you can intact use the combination of two foreign keys as a primary key. This works because we will never have two duplicate rows within the intermediary table and the two foreign keys work as a compound key because of this. We finally discussed primary keys and foreign keys. Primary keys are used to keep each row inside of a table unique. If this key is a computer generated number it is known as a surrogate key, otherwise it is known as a natural key. Natural keys have real world meaning. For example, a social security number may work, or an email address (in some situations), etc. Whichever type of key you choose is solely up to you and/or the company you may be working for. HELP ME! http://www.patreon.com/calebcurry Subscribe to my newsletter: http://bit.ly/JoinCCNewsletter Donate!: http://bit.ly/DonateCTVM2. ~~~~~~~~~~~~~~~Additional Links~~~~~~~~~~~~~~~ More content: http://CalebCurry.com Facebook: http://www.facebook.com/CalebTheVideoMaker Google+: https://plus.google.com/+CalebTheVideoMaker2 Twitter: http://Twitter.com/calebCurry Amazing Web Hosting - http://bit.ly/ccbluehost (The best web hosting for a cheap price!)
Views: 49647 Caleb Curry
SQL Error: Cannot insert the value NULL into column ID
 
02:00
https://codedocu.com/Details?d=2139&a=10&f=352&l=0 System.Data.SqlClient.SqlException occurred HResult=0x80131904 Message=Cannot insert the value NULL into column 'IDDetail', table column does not allow nulls. INSERT fails.
Views: 8258 CodeDocu_com
Oracle interview question difference between null functions
 
07:23
Difference between NVL,NVL2, NULLIF and COALESCE NVL function will check whether the first input parameter is null, if first input parameter is null then the function returns the second parameter value as output. NVL2 function will check the first parameter, and return second parameter if the first parameter is not null, otherwise returns third parameter. NULLIF will compare the input parameters ( first and second parameter ), and returns NULL of both are same, otherwise returns the first parameter value. COALESCE, returns the first not null expression in the given input parameters. -------------------------------------------------------------------------------------------------------- List of all the SQL and PLSQL interview questions https://easy-learning-tech.blogspot.com/p/oracle-sql-plsql-interview-questions.html
Views: 2072 Siva Academy
auto increment in sql oracle - ( Auto increment field )
 
03:07
auto increment in sql oracle ----------------------------------------------- CREATE table customers ( customer_id int not null, customer_name varchar(50), primary key (customer_id) ); create sequence customer_id minvalue 1 start with 1 cache 10; insert into customers values(customer_id.nextval,'maxwel'); -- to drop sequence drop sequence customer_id
Views: 9890 Data Disc
Unique and Non Unique Indexes in sql server   Part 37
 
11:02
In this video we will learn about 1. What is a Unique Index 2. Difference between unique index and unique constraint Text version of the video http://csharp-video-tutorials.blogspot.com/2012/09/unique-and-non-unique-indexes-part-37.html Slides http://csharp-video-tutorials.blogspot.com/2013/09/part-37-unique-non-unique-indexes.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 221616 kudvenkat
How to Install Oracle! !! Database Training
 
01:50
For Complete Database Training Details Visit: http://www.qaonlinetraining.com http://infotek-solutions.com/ Delivery Method: Instructor led classroom and Online Training supported by world class Learning management system which automate all flow of lectures, videos, assignments, forums, quizzes and interview process. Class Schedule: Week-ends and Weekdays Contact Us: 571-437-0652, Mail Us: [email protected] Training Locations at : Ashburn / Fairfax / Maryland Office Address: 12801 Worldgate Dr #500, Herndon, VA 20170 Overview of Oracle DBA Training Oracle as a flexible, complex & robust RDBMS The evolution of hardware and the relation to Oracle Different DBA job roles (VP of DBA, developer DBA, production DBA, database babysitter) The changing job role of the Oracle DBA Environment management (network, CPU, disk and RAM) Instance management (managing SGA regions) Oracle table and index management Instance Architecture Instance vs. database Components of an instance Creating the OFA file structure ($DBA, bdump, udump, pfile) Oracle Instance Internals SGA vs. PGA Background processes Interfaces with server and disk I/O subsystem Using SQL*Plus for DBA management Connecting and executing SQL Using the “as sysdba” syntax Overview of SQL*Plus DBA commands (startup, etc.) Control file, UNDO and REDO management Explaining the use of control files Listing the Contents of the control File File locations for control Files Obtaining Control File Information Listing control file contents Displaying and Creating Undo segments Altering Undo Segments Determining the Number and Size of Undo segments Understanding flashback technology Troubleshooting Undo – snapshot too old Redo log concepts for recovery Online redo log (log_buffer) online redo logs and archived redo logs Oracle ARCH and LGWR background processes Redo log dictionary queries Redo log switch frequency and performance Multiplexing the Online Redo Log Files Archiving the Oracle Redo Logs Recovery using the redo log files User and privilege management The three security methods (VPD, Grant security/role-based security, grant execute) Creating New Database Users Using pre-spawned Oracle connections Auditing User activity Identifying System and Object Privileges Granting and Revoking Privileges Creating and Modifying Roles Displaying user security Information from the Data Dictionary Overview of instance management Parameter files (init.ora, listener.ora, tnsnames.ora) Rules for sizing SGA components Automated Oracle memory management (AMM) Initialization file management Creating the init.ora file Using spfile Displaying init.ora values with v$parameter Oracle*Net configuration Creating the listener.ora file Creating the tnsnames.ora file Data buffer configuration & sizing Inside the Oracle data buffers Using the KEEP pool Monitoring buffer effectiveness Using multiple blocksizes (multiple buffer pools) Shared pool and PGA configuration & Sizing Shared pool concepts and components Understanding the library cache Relieving shared pool contention Overview of PGA for sorting and hash joins Using sort_area_size, hash_area_size and pga_aggregate_target Troubleshooting network connectivity Verifying network connectivity with ping and tnsping Testing database links Oracle tables, views and materialized views Types of Oracle tables (regular, IOT, sorted hash clusters, nested tables) Oracle Views Oracle materialized views Oracle indexes Types of Oracle indexes (b-tree, bitmap, bitmap join index) Creating B*-Tree, bitmap and function-based Indexes Function-based indexes Finding indexing opportunities Index maintenance Oracle constraints Costs & benefits of constraints Types of Oracle indexes constraints (check, not null, unique, PK, FK) Cascading constraints Schema, File & tablespace management Describing the relationship between data files, tablespaces and table Understanding Oracle segments Creating Tablespaces – using the autoextend option Changing the Size of Tablespaces – alter database datafile command Defining a TEMP tablespace Changing the default storage Settings for a tablespace Review of the storage parameters in DBA views (ASM, ASSM, pctfree, pctused and freelists). Monitoring Chained rows (fetch continued rows) Monitoring Insert and Update performance (pctused, APPEND) Database Maintenance Reason for reorgs – chained rows, imbalanced freelists Reorganizing Tables using Export and Import Using CTAS to reorganize data Index rebuilding Backup & Recovery overview (hot & cold Backups, RMAN, block change tracking) Oracle DBA Utilities Data pump (Imp and exp utilities) SQL*Loader LogMiner Flashback DataGuard Oracle DBA utilities – Oracle dbms packages (dbms_redefinition)
Oracle SQL Tutorial For Beginners | Oracle SQL Online Training - Session 1
 
52:39
Course : Oracle SQL Online Training Mode of Training : Online Duration : 40 Hours Timings : Flexible Oracle SQL Online Training Demo Registration Link : http://svsoftsolutions.com/demo.aspx Introduction to SQL What is SQL? What Can SQL do? RDBMS SQL Syntax Database Tables SQL Statements Overview of Most Important SQL Commands SELECT UPDATE DELETE INSERT CREATE TABLE ALTER TABLE DROP TABLE CREATE INDEX DROP INDEX SQL SELECT Statement SELECT syntax Demo Database SELECT Column Example SELECT * Example SQL Distinct SELECT DISTINCT Statement SELECT DISTINCT Syntax SELECT DISTINCT Example SQL WHERE Clause WHERE Clause WHERE Clause Example Operators in the WHERE Clause SQL AND & OR Operators AND Operator Example OR Operator Example Combining AND & OR SQL ORDER BY ORDER BY Syntax ORDER BY Example ORDER BY DESC Example ORDER BY Several Column Examples SQL Insert Into INSERT INTO Syntax INSERT INTO Examples Insert Data into Specified Columns SQL UPDATE UPDATE Syntax UPDATE Example Watch out UPDATE statement. SQL DELETE DELETE Syntax DELETE Examples Delete All the Data SQL Aliases SQL Alias Syntax for Columns Alias Example for Table Columns Alias Example for Tables. SQL Joins Different SQL JOINs INNER JOIN LEFT OUTER JOIN RIGHT OUTER JOIN FULL OUTER JOIN SQL UNION UNION Syntax UNION Example UNION ALL Syntax UNION ALL Example SQL Insert Into Select INSERT INTO SELECT Syntax INSERT INTO SELECT Examples SQL Create Table CREATE TABLE Syntax CREATE TABLE Example SQL Constraints CREATE TABLE + CONSTRAINT Syntax NOT NULL Constraint UNIQUE Constraint UNIQUE Constraint on CREATE TABLE UNIQUE Constraint on ALTER TABLE To DROP a UNIQUE Constraint PRIMARY KEY Constraint PRIMARY KEY Constraint on CREATE TABLE PRIMARY KEY Constraint on ALTER TABLE To DROP a PRIMARY KEY Constraint FOREIGN KEY Constraint FOREIGN KEY Constraint on CREATE TABLE FOREIGN KEY Constraint on ALTER TABLE To DROP a FOREIGN KEY Constraint CHECK Constraint CHECK Constraint on CREATE TABLE CHECK Constraint on ALTER TABLE To DROP a CHECK Constraint DEFAULT Constraint on CREATE TABLE DEFAULT Constraint on ALTER TABLE To DROP a DEFAULT Constraint SQL Create Index CREATE INDEX Syntax CREATE UNIQUE INDEX Syntax CREATE INDEX Example SQL DROP Command The DROP INDEX Statement The DROP TABLE Statement The DROP DATABASE Statement The TRUNCATE TABLE Statement SQL ALTER Command The ALTER TABLE Statement ALTER TABLE Example Change Data Type Example DROP COLUMN Example SQL VIEWS CREATE VIEW Statement CREATE VIEW Syntax CREATE VIEW Examples CREATE OR REPLACE VIEW Syntax Dropping a View SQL NULL Values Working with NULL Values IS NULL IS NOT NULL SQL NULL Functions NVL COALESCE For more details visit our website : www.svsoftsolutions.com Or reach us @ USA : +1-845-915-8712 (Toll Free), India : +91-9642373173
Views: 3283 SV Soft Solutions
SQL SERVER 2017 TUTORIAL 8 : Constraints
 
07:35
SQL constraints are used to specify rules for the data in a table. Constraints let you define the way the Database Engine automatically enforces the integrity of a database. Constraints define rules regarding the values allowed in columns and are the standard mechanism for enforcing integrity. Using constraints is preferred to using DML Triggers, rules, and defaults. The query optimizer also uses constraint definitions to build high-performance query execution plans. Constraints are used to limit the type of data that can go into a table. This ensures the accuracy and reliability of the data in the table. If there is any violation between the constraint and the data action, the action is aborted. Constraints can be column level or table level. Column level constraints apply to a column, and table level constraints apply to the whole table. The following constraints are commonly used in SQL: NOT NULL - Ensures that a column cannot have a NULL value UNIQUE - Ensures that all values in a column are different PRIMARY KEY - A combination of a NOT NULL and UNIQUE. Uniquely identifies each row in a table FOREIGN KEY - Uniquely identifies a row/record in another table CHECK - Ensures that all values in a column satisfies a specific condition DEFAULT - Sets a default value for a column when no value is specified INDEX - Used to create and retrieve data from the database very quickly
Views: 2612 G Tech
Creating an Index in Oracle SQL
 
03:36
This video shows how to Create an index in Oracle SQL . Try to share these videos for poor students and subscribe this channel for more upcoming other technical videos.
Views: 31 Technology mart
SQL Server 28 - Composite Primary Key
 
04:55
The previous video had these tables: CREATE TABLE Species( ID INT PRIMARY KEY IDENTITY, Species VARCHAR(50) NOT NULL UNIQUE, FriendlyName VARCHAR(50) NOT NULL ); CREATE TABLE Animals( ID INT PRIMARY KEY IDENTITY, Name VARCHAR(50) NOT NULL, Species INT NOT NULL REFERENCES Species(ID), ContactEmail VARCHAR(50) NOT NULL UNIQUE ); These column attributes are all examples of constraints. To be more specific, they are known as column-level constraints. Sometimes you need to create what is known as a table-level constraint. To illustrate this, we are going to create a new table that shows this in action. Remember that we are trying to create an animal dating site. A specific animal can create an account on our website and say what kind of species he or she is interested in. One specific animal can be interested in multiple species and an individual species can be liked by many animals. Therefore, it is a many to many relationship. We already have a Species table and an Animals table, so we need an intermediary table to associate animals with species: CREATE TABLE Interests( AnimalID INT NOT NULL REFERENCES Animals(ID), SpeciesID INT NOT NULL REFERENCES Species(ID) ); But now, we want to create a composite primary key, the combination of both columns. A column-level attribute is not capable of doing this because it is associated with just one column. Let's create a table-level constraint. To do this we add the constraint as if it's another column: CREATE TABLE Interests( AnimalID INT NOT NULL REFERENCES Animals(ID), SpeciesID INT NOT NULL REFERENCES Species(ID), PRIMARY KEY (AnimalID, SpeciesID) ); The downside here is that we cannot create a foreign key to reference this composite key. If for some reason we have to be able to reference an individual interest in another table, we would create an ID column and put a UNIQUE constraint on the combination of AnimalID and SpeciesID. Then we could reference an individual ID. Now, in SSMS, inside of our tables key folder you can find the composite key. Unfortunately, SSMS defaults to a pretty ugly name for our primary key constraint. Fortunately, we can actually give names to our constraints. That's what we will be doing in the next video. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Support me! http://www.patreon.com/calebcurry Subscribe to my newsletter: http://bit.ly/JoinCCNewsletter Donate!: http://bit.ly/DonateCTVM2. ~~~~~~~~~~~~~~~Additional Links~~~~~~~~~~~~~~~ More content: http://CalebCurry.com Facebook: http://www.facebook.com/CalebTheVideoMaker Google+: https://plus.google.com/+CalebTheVideoMaker2 Twitter: http://twitter.com/calebCurry Amazing Web Hosting - http://bit.ly/ccbluehost (The best web hosting for a cheap price!)
Views: 13071 Caleb Curry
How to implement VPD in Oracle Database (Part 1)
 
12:37
How to implement VPD (Virtual Private Database) in Oracle Database(9i,10g,11g,12c) Enterprise Edition. PART 1 Video links: Part 1 https://youtu.be/JVvtvh3cN1I Part 2 https://youtu.be/xLcin_Wgbvs Part 3 https://youtu.be/mE1cSbmEwnQ This is Part of Oracle Advance Security. Please view my earlier videos on how to create a database , if you are not having a database. 1)First we will create the users needed for our environment a)Owner of the schema which will have the objects or tables b)security admin user c)non owner user1 & user2 which will have limited access as per data in the rows (here user1 will have access to data with HR and user2 with FINANCE) Object owner creation: -------------- CREATE USER schemaowner IDENTIFIED BY schemaowner DEFAULT TABLESPACE users TEMPORARY TABLESPACE temp; GRANT connect, resource TO schemaowner; alter user schemaowner quota unlimited on users; security admin user creation: -------------- CREATE USER SEC_ADM IDENTIFIED BY sec_adm default tablespace users temporary tablespace TEMP; GRANT CONNECT, RESOURCE TO sec_adm; alter user sec_adm quota unlimited on users; garnts for the sec_adm user: ------------- GRANT CREATE SESSION,CREATE ANY CONTEXT,CREATE PROCEDURE,CREATE TRIGGER, ADMINISTER DATABASE TRIGGER TO SEC_ADM; GRANT EXECUTE ON DBMS_SESSION TO SEC_ADM; GRANT EXECUTE ON DBMS_RLS TO SEC_ADM; create user with restricted access on table: ----------------------- CREATE USER user1 IDENTIFIED BY user1 DEFAULT TABLESPACE users TEMPORARY TABLESPACE temp; GRANT connect, resource TO user1; CREATE USER user2 IDENTIFIED BY user2 DEFAULT TABLESPACE users TEMPORARY TABLESPACE temp; GRANT connect, resource TO user2; Now we will log in as schemaowner and create one tables : ------------------- CONN schemaowner/schemaowner This table is the table which contains the secure as well as un-restricted data CREATE TABLE user_data (column1 VARCHAR2(50) NOT NULL, user_id VARCHAR2(30) NOT NULL); Now to access this table from other schema we need to give the select and insert privs to: GRANT SELECT, INSERT ON user_data TO sec_adm,user1, user2;
Views: 1119 OracleDBA
Locking in Oracle | Oracle SQL Tutorial Videos | Mr.Vijay Kumar
 
21:57
Locking in Oracle | Oracle SQL Tutorial Videos | Mr.Vijay Kumar ** For Online Training Registration: https://goo.gl/r6kJbB ► Call: +91-8179191999 💡 Visit Our Website for Classroom Training: https://nareshit.in/oracle-training/ 💡 For Online Training: https://nareshit.com/oracle-online-training/ #Oracle #Training #CourseVideos -------------------------- 💡 About NareshIT: "Naresh IT is having 14+ years of experience in software training industry and the best Software Training Institute for online training, classroom training, weekend training, corporate training of Hadoop, Salesforce, AWS, DevOps, Spark, Data Science, Python, Tableau, RPA , Java, C#.NET, ASP.NET, Oracle, Testing Tools, Silver light, Linq, SQL Server, Selenium, Android, iPhone, C Language, C++, PHP and Digital Marketing in USA, Hyderabad, Chennai and Vijayawada, Bangalore India which provides online training across all the locations -------------------------- 💡 Our Online Training Features: 🎈 Training with Real-Time Experts 🎈 Industry Specific Scenario’s 🎈 Flexible Timings 🎈 Soft Copy of Material 🎈 Share Videos of each and every session. -------------------------- 💡 Please write back to us at 📧 [email protected]/ 📧 [email protected] or Call us at the USA: ☎+1404-232-9879 or India: ☎ +918179191999 -------------------------- 💡 Check The Below Links ► For Course Reg: https://goo.gl/r6kJbB ► Subscribe to Our Channel: https://goo.gl/q9ozyG ► Circle us on G+: https://plus.google.com/+NareshIT ► Like us on Facebook: https://www.facebook.com/NareshIT ► Follow us on Twitter: https://twitter.com/nareshitek ► Follow us on Linkedin: https://goo.gl/CRBZ5F ► Follow us on Instagram: https://goo.gl/3UXYK3
Views: 24706 Naresh i Technologies
Part 6   Transform rows into columns in sql server
 
08:53
Link for all dot net and sql server video tutorial playlists http://www.youtube.com/user/kudvenkat/playlists Link for slides, code samples and text version of the video http://csharp-video-tutorials.blogspot.com/2014/06/part-6-transform-rows-into-columns-in.html This is another common sql server interview question. We will be using Countries table in this example. SQL to create the table Create Table Countries ( Country nvarchar(50), City nvarchar(50) ) GO Insert into Countries values ('USA','New York') Insert into Countries values ('USA','Houston') Insert into Countries values ('USA','Dallas') Insert into Countries values ('India','Hyderabad') Insert into Countries values ('India','Bangalore') Insert into Countries values ('India','New Delhi') Insert into Countries values ('UK','London') Insert into Countries values ('UK','Birmingham') Insert into Countries values ('UK','Manchester') Here is the interview question. Write a sql query to transpose rows to columns. Using PIVOT operator we can very easily transform rows to columns. Select Country, City1, City2, City3 From ( Select Country, City, 'City'+ cast(row_number() over(partition by Country order by Country) as varchar(10)) ColumnSequence from Countries ) Temp pivot ( max(City) for ColumnSequence in (City1, City2, City3) ) Piv
Views: 208329 kudvenkat
Oracle - SQL - Unique Constraint
 
07:50
Oracle - SQL - Unique Constraint Watch more Videos at https://www.tutorialspoint.com/videotutorials/index.htm Lecture By: Mr. Anadi Sharma, Tutorials Point India Private Limited.
CREATE TABLE WITH CONSTRAINTS - ORACLE - SQL
 
20:35
Create table , add constraints : primary key constraint, foreign key constraint, check constraint, unique constraint, specifying the table space for index, modifying table, dropping table Oracle 10g
Views: 10030 R.N.A. Creation
SQL Server 15 - Composite Key
 
07:57
An interesting thing you can do with primary keys is that you can make a combination of columns the primary key. This is important when more than one column is required to make something unique. In an intermediary table, instead of having an association ID, we can have the combination of two rows as the primary key. This is known as either a compound or composite primary key. In the situation of using natural keys, composite keys are more common. For example, you could have a shopping website that allows multiple people from the same household to use a certain coupon you sent out. In this situation, you could use the address and the person's name as the natural primary key. What is the difference between a primary key and a column that has UNIQUE and NOT NULL constraints? The primary difference has to do with indexing. When you create a primary key, the column will automatically be indexed. This means that working with this data is faster. Now, we haven't talked a ton on indexes, but by default this will create a clustered index. UNIQUE constraints are also indexed by default, but the default index for a UNIQUE constraint is a non-clustered index. Clustered indexes determine how the table is actually stored, while non clustered indexes will make a sorted list that has reference to the data. This is not a life changing difference because these can actually be changed. We will discuss all of the details of indexing in future videos. As a side note, the IDENTITY column is not automatically indexed. How do we reference primary keys? This requires what is known as a foreign key, which we will discuss in the next video. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Support me! http://www.patreon.com/calebcurry Subscribe to my newsletter: http://bit.ly/JoinCCNewsletter Donate!: http://bit.ly/DonateCTVM2. ~~~~~~~~~~~~~~~Additional Links~~~~~~~~~~~~~~~ More content: http://CalebCurry.com Facebook: http://www.facebook.com/CalebTheVideoMaker Google+: https://plus.google.com/+CalebTheVideoMaker2 Twitter: http://twitter.com/calebCurry Amazing Web Hosting - http://bit.ly/ccbluehost (The best web hosting for a cheap price!)
Views: 12716 Caleb Curry
1 of 6 SQL Advanced with Oracle - Equi-joins, one-sided outer joins, plus notation
 
08:37
This video shows examples of equi-joins (the default when you use two tables in a query), one-sided outer joins using the JOIN operator in the FROM clause, and the use of the "plus notation" in Oracle in the WHERE clause (another way to do a one-sided outer join). There is also an example of using a one-sided outer join with the "is null" criterion in the WHERE clause. (1 of 6) There is also an "SQL Fundamentals" series. (Search for "databasemec" for tutorials using SQL Server.)
Views: 40752 Jennifer Kreie
Validation Rule: Is Not Null
 
02:30
Validation Rule: Is Not Null
Views: 9219 Perins Elearning
A case study on using Composite Unique Indexes in Oracle on nullable columns
 
00:57
We use unique indexes in Oracle to maintain distinct values in columns. Let us explore a case where we have Unique Indexes on(combination of) two or more columns in a table in Oracle, where one column has mostly null values.
Views: 7 Peeush Trikha
Dynamic SQL in Stored Procedure
 
09:32
In this video we will discuss, using dynamic sql in a stored procedure and it's implications from sql injection perspective. We will discuss performance implications of using dynamic sql in a stored procedure in a later video. Text version of the video http://csharp-video-tutorials.blogspot.com/2017/04/dynamic-sql-in-stored-procedure.html Slides http://csharp-video-tutorials.blogspot.com/2017/04/dynamic-sql-in-stored-procedure_11.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All SQL Server Tutorial Videos https://www.youtube.com/playlist?list=PL08903FB7ACA1C2FB All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists Consider the following stored procedure "spSearchEmployees". We implemented this procedure in Part 139 of SQL Server tutorial. This stored procedure does not have any dynamic sql in it. It is all static sql and is immune to sql injection. Create Procedure spSearchEmployees @FirstName nvarchar(100) = NULL, @LastName nvarchar(100) = NULL, @Gender nvarchar(50) = NULL, @Salary int = NULL As Begin Select * from Employees where (FirstName = @FirstName OR @FirstName IS NULL) AND (LastName = @LastName OR @LastName IS NULL) AND (Gender = @Gender OR @Gender IS NULL) AND (Salary = @Salary OR @Salary IS NULL) End Go Whether you are creating your dynamic sql queries in a client application like ASP.NET web application or in a stored procedure, you should never ever concatenate user input values. Instead you should be using parameters. Notice in the following example, we are creating dynamic sql queries by concatenating parameter values, instead of using parameterized queries. This stored procedure is prone to SQL injection. Let's prove this by creating a "Search Page" that calls this procedure. Create Procedure spSearchEmployeesBadDynamicSQL @FirstName nvarchar(100) = NULL, @LastName nvarchar(100) = NULL, @Gender nvarchar(50) = NULL, @Salary int = NULL As Begin Declare @sql nvarchar(max) Set @sql = 'Select * from Employees where 1 = 1' if(@FirstName is not null) Set @sql = @sql + ' and FirstName=''' + @FirstName + '''' if(@LastName is not null) Set @sql = @sql + ' and LastName=''' + @LastName + '''' if(@Gender is not null) Set @sql = @sql + ' and Gender=''' + @Gender + '''' if(@Salary is not null) Set @sql = @sql + ' and Salary=''' + @Salary + '''' Execute sp_executesql @sql End Go Add a Web Page to the project that we have been working with in our previous video. Name it "DynamicSQLInStoredProcedure.aspx". Copy and paste the HTML and code available on my blog at the following link http://csharp-video-tutorials.blogspot.com/2017/04/dynamic-sql-in-stored-procedure.html At this point, run the application and type the following text in the "Firsname" text and click "Search" button. Notice "SalesDB" database is dropped. Our application is prone to SQL injection as we have implemented dynamic sql in our stored procedure by concatenating strings instead of using parameters. ' Drop database SalesDB -- In the following stored procedure we have implemented dynamic sql by using parameters, so this is not prone to sql injecttion. This is an example for good dynamic sql implementation. Create Procedure spSearchEmployeesGoodDynamicSQL @FirstName nvarchar(100) = NULL, @LastName nvarchar(100) = NULL, @Gender nvarchar(50) = NULL, @Salary int = NULL As Begin Declare @sql nvarchar(max) Declare @sqlParams nvarchar(max) Set @sql = 'Select * from Employees where 1 = 1' if(@FirstName is not null) Set @sql = @sql + ' and [email protected]' if(@LastName is not null) Set @sql = @sql + ' and [email protected]' if(@Gender is not null) Set @sql = @sql + ' and [email protected]' if(@Salary is not null) Set @sql = @sql + ' and [email protected]' Execute sp_executesql @sql, N'@FN nvarchar(50), @LN nvarchar(50), @Gen nvarchar(50), @sal int', @[email protected], @[email protected], @[email protected], @[email protected] End Go On the code-behind page, use stored procedure spSearchEmployeesGoodDynamicSQL instead of spSearchEmployeesBadDynamicSQL. We do not have to change any other code. At this point run the application one more time and type the following text in the "Firstname" textbox and click the "Search" button. ' Drop database SalesDB -- Notice "SalesDB" database is not dropped, So in this case our application is not succeptible to SQL injection attack. Summary : Whether you are creating dynamic sql in a client application (like a web application) or in a stored procedure always use parameters instead of concatnating strings. Using parameters to create dynamic sql statements prevents sql injection.
Views: 38152 kudvenkat
47. UNIQUE KEY in SQL (Hindi)
 
16:42
Please Subscribe Channel Like, Share and Comment Visit : www.geekyshows.com
Views: 23764 Geeky Shows
How Many Indexes Are Too Many?: Finding All The Red Sweets Part 5
 
10:58
Every index you add to a table increases its storage requirements and DML overheads. So it's a good idea to create as few as possible. When you have two or more indexes using the same columns, you may be able to get away with just one. But how do you decide which to keep? This video discusses how to analyze your queries so you can cut the number of indexes you create. ============================ The Magic of SQL with Chris Saxon Copyright © 2015 Oracle and/or its affiliates. Oracle is a registered trademark of Oracle and/or its affiliates. All rights reserved. Other names may be registered trademarks of their respective owners. Oracle disclaims any warranties or representations as to the accuracy or completeness of this recording, demonstration, and/or written materials (the “Materials”). The Materials are provided “as is” without any warranty of any kind, either express or implied, including without limitation warranties or merchantability, fitness for a particular purpose, and non-infringement.
Views: 2470 The Magic of SQL
UNIQUE AND NON-UNIQUE INDEX IN SQL (URDU / HINDI)
 
20:44
SUBSCRIBE FOR MORE AND PRESS BELL ICON TO GET LATEST VIDEO UPDATES...
Views: 568 Learning Never Ends
Foreign Key | Database Management System
 
06:29
To ask your doubts on this topic and much more, click on this Direct Link: http://www.techtud.com/video-lecture/lecture-foreign-key IMPORTANT LINKS: 1) Official Website: http://www.techtud.com/ 2) Virtual GATE: http://virtualgate.in/login/index.php Both of the above mentioned platforms are COMPLETELY FREE, so feel free to Explore, Learn, Practice & Share! Our Social Media Links: Facebook Page: https://www.facebook.com/techtuduniversity Facebook Group: https://www.facebook.com/groups/virtualgate Google+ Page: https://plus.google.com/+techtud/posts Last but not the least, SUBSCRIBE our YouTube channel to stay updated about the regularly uploaded new videos.
Views: 281778 Techtud